1. Field of the Invention
This invention relates to an electric source control device providing a function which prevents battery death for a vehicle. More particularly, this invention relates to a vehicle electric source control device providing a function which prevents battery death caused by leaving interior dome lamps or door lamps to be lighted.
2. Prior Art
A vehicle is usually equipped with an interior dome lamp which throws light over a vehicle interior, and door lamps which throw light on people's foot areas when they get in or get out of the vehicle and inform following vehicles that a door is opened.
The above-mentioned interior dome lamp is controlled by a switch which is changeable, having an "ON mode", an "OFF mode" and a "DOOR mode". In case the switch is in the "ON mode", the interior dome lamp is on at all times. When the switch is changed to "OFF mode", the interior dome lamp is off. Moreover, when the switch is changed to "DOOR mode", the interior dome lamp is on when any door is opened, and the interior dome lamp is off when all doors are closed.
Also, the interior dome lamp is left to be on during a predetermined time after all doors are closed in order to make it much easier for a driver to prepare for driving at night.
An Electronic Control Unit (hereinafter referred to as ECU) usually performs the above-mentioned control. The ECU receives a door switch state input and generates an output in response to it, which then operates a lamp main relay and switches the interior dome lamp etc. on or off according to the output.
In the above-stated conventional interior dome lamp control system, battery death is sometimes caused because the interior dome lamp is left on.
There is, for example, a case that a driver switches on the interior dome lamp or the map lamp in a dark place, for example in a tunnel, however after getting out of the tunnel he or she forgets to switch them off and parks the vehicle where surroundings are light.
Also, in case the lamp switch is changed to "DOOR mode, when a driver leaves a vehicle he or she may not realize the door is not completely closed.
The present invention takes the above-mentioned matter into consideration, and the object is to provide a vehicle electric source control device which prevents battery death caused by leaving lamps lighted or by a door that is not completely closed.